armhook

noun3

1. •
   A movement in which two people hook arms at the elbow and turn around each other.
2. •
   A hook-like projection on the arm of a cephalopod, such as on the armhook squid (Gonatus fabricii).

   • Furthermore the armhooks of the Belemnoidea show a micro-texture and a mode of growth similar to the horny inner rings of the suckers of the Decabrachia. — 1989
3. •
   A hook for maneuvering something using the arm.

   • By the arrangement of these armhooks, it is possible for nurses to open doors while both hands are occupied. — 1919